Manchester concert explosion

Emergency assistance

Emergency responders assist an injured woman near the Manchester Arena after a deadly explosion during an Ariana Grande concert in Manchester, England, on May 22, 2017.

Credit: Rex Features via AP Images

Injured man

An injured man is seen near the Manchester Arena after an explosion during an Ariana Grande concert on May 22, 2017. More than 20 people were killed and dozens wounded.

Credit: Rex Features via AP Images

Inside the arena

Still image from video shows people fleeing Manchester Arena after an explosion. Singer Ariana Grande had been performing for a sold-out crowd.

Credit: TWITTER.COM/HANNAWWH/via Reuters TV

Concertgoers flee

People running down stairs as they attempt to exit the Manchester Arena after the explosion on May 22, 2017. The still image was taken from video shot by concertgoer Zach Bruce, who told CBS News he escaped after hearing a "loud bang." He added, "I didn't know what was going on."

Credit: @ZACH_BRUCE via Reuters TV

Police response

Heavily armed police at Manchester Arena in northern England after reports of an explosion at the venue during an Ariana Grande concert on May 22, 2017. Officials later confirmed more than 20 concertgoers were killed and dozens wounded. A representative said the singer was not injured.

Credit: Peter Byrne / AP

Bomb scene

Helpers attend to injured people inside the Manchester Arena after a blast on May 22, 2017. Police said a suicide bomber blew himself up at an Ariana Grande concert as it ended Monday night.

Credit: Press Association via AP

Manchester street scene

Police and other emergency service workers are seen near the Manchester Arena after an explosion during an Ariana Grande performance. Many young people were at the concert.

Credit: Rex Features via AP Images

Armed police

Heavily armed police respond to reports of an explosion at Manchester Arena during an Ariana Grande concert on May 22, 2017.

Credit: Peter Byrne / AP

Police and concertgoers

Police and fans talk in the street near the Manchester Arena in Manchester, England, following a deadly explosion during an Ariana Grande concert. Greater Manchester Police confirmed there were fatalities and warned people to stay away from the area.

Credit: Dave Thompson / Getty Images

Manchester Arena scene

People fled the Manchester Arena after an explosion during an Ariana Grande concert in the city in northern England.

Credit: Rex Features via AP Images

Emergency treatment

Members of the public receive treatment from emergency service staff at Victoria Railway Station near the Manchester Arena, following a deadly explosion during an Ariana Grande concert on May 22, 2017.

Credit: Dave Thompson / Getty Images

Outside Manchester Arena

People fled the Manchester Arena after an explosion during an Ariana Grande concert.

Credit: Rex Features via AP Images

Emergency response

Police stand by a cordoned-off street near the Manchester Arena after an explosion during an Ariana Grande concert.

Credit: Dave Thompson / Getty Images

Ariana Grande

A spokesman said Ariana Grande was "OK" following an explosion at her concert in Manchester, England, on May 22, 2017.

The singer is seen here in a photo from the American Music Awards in Los Angeles on Nov. 20, 2016.

Credit: Mario Anzuoni/Reuters

Police and concertgoers

Emergency services personnel speak to people outside Manchester Arena after a deadly explosion at the venue during an Ariana Grande concert.

Credit: Peter Byrne / AP

Manchester concertgoers

Concert goers fled the Manchester Arena in after an explosion during an Ariana Grande concert, May 22, 2017.

Credit: Reuters

Emergency services

Police and ambulances outside Manchester Arena after an explosion at the venue during an Ariana Grande concert on May 22, 2017. Officials said more than 20 people were killed and dozens wounded.

Credit: Peter Byrne / AP

First reponders

A police van and an ambulance are seen outside the Manchester Arena after an explosion during an Ariana Grande concert at the venue in Manchester, northern England, May 22, 2017.

Credit: Reuters

Forensic investigators

Forensics investigators at work outside the Manchester Arena on May 23, 2017, the morning after the deadly explosion at an Ariana Grande concert.

Credit: Darren Staples / Reuters

"Pray for Manchester"

A woman walks past an electronic advertising board displaying a U.K. flag and the words "Pray For Manchester," close to the Manchester Arena in northwest England on May 23, 2017, following a deadly terror attack at an Ariana Grande concert.

Credit: Ben Stansall / AFP/Getty Images

Forensic investigation

Police forensic officers leave the Manchester Arena on May 23, 2017 as they investigate the scene of the explosion, which occurred the night before as concertgoers were leaving an Ariana Grande concert.

Credit: Dave Thompson / Getty Images

Manchester reunion

A man embraces a woman and a teenager as he collects them from the Park Inn Hotel where they were given refuge after Monday night's explosion at the Manchester Arena.

Credit: Christopher Furlong / Getty Images

Young victim

Saffie Roussos, 8, was identified as one of the victims of the attack at Manchester Arena. The Guardian reports she was attending the concert with her mother and sister, who were both wounded.

"Saffie was simply a beautiful little girl in every aspect of the word. She was loved by everyone and her warmth and kindness will be remembered fondly," said Chris Upton, the head teacher at her primary school.

Credit: Press Association via AP

Bomb victim posed with Ariana Grande

18-year-old Georgina Callander was the first identified victim from the Manchester Arena bombing. These photos of her with singer Ariana Grande were taken in 2015.

Credit: via Instagram

Flowers for the victims

A woman lays flowers at a memorial for the victims of the Manchester Arena attack in central Manchester, England, May 23, 2017.

Credit: Darren Staples / Reuters

Police at memorial

Police officers relocate floral tributes in St Ann's Square in Manchester, northwest England, on May 23, 2017, following a deadly terror attack at the concert at the Manchester Arena the night before.

Credit: Ben Stansall / AFP/Getty Images

Prime Minister visits

Britain's Prime Minister Theresa May meets Chief Constable of Greater Manchester Police Ian Hopkins on May 23, 2017 in Manchester, England. May held an emergency meeting with government officials the morning following a suicide attack at Manchester Arena that killed more than 20 concertgoers.

Credit: Leon Neal / Getty Images

#TurnToLove

People hold up signs which say "#TurnToLove #ForManchester" during a vigil for the victims of the Manchester Arena terror attack in Trafalgar Square, London, on May 23, 2017.

Credit: Jack Taylor / Getty Images

Moment of silence

Queen Elizabeth II and her husband Prince Philip, Duke of Edinburgh observe a minute of silence at Buckingham Palace on May 23, 2017, in honor of the victims of the attack at Manchester Arena the night before.

Credit: WPA Pool / Getty Images

Manchester memorial

A man and a child light a candle alongside floral tributes in Albert Square in Manchester, England, on May 23, 2017, in memory of those killed and injured in the May 22 terror attack at the Ariana Grande concert at the Manchester Arena.

Credit: Oli Scarff / AFP/ Getty Images

"We are strong"

A man writes a message on the pavement in central Manchester, England, May 23, 2017.

Credit: Darren Staples / Reuters

Manchester memorial

Members of the public attend a vigil to honor at Albert Square in Manchester, England, on May 23, 2017, to honor the victims of the terror attack at the Ariana Grande concert at Manchester Arena the night before.

Credit: Jeff J Mitchell / Getty Images

Sidewalk memorial

Flowers and messages for the victims of the Manchester Arena attack are seen in central Manchester, England, May 23, 2017.

Credit: Darren Staples / Reuters

European memorial

Flowers for victims of the deadly suicide bombing at Manchester Arena are seen in front of the British embassy in Berlin, Germany, May 23, 2017.